A silver halide photographic light-sensitive material is generally composed of a support having layer(s) containing a hydrophilic colloid such as gelatin, etc., as a binder on at least one surface thereof. Such a hydrophilic colloid layer, however, has a defect that the layer is liable to be stretched or shrunk with changes in humidity and/or temperature.
The dimensional change of a photographic light-sensitive material caused by stretching or shrinkage of the hydrophilic colloid layer causes serious defects in the case of a photographic light-sensitive material for printing, which is required to reproduce dot images for multicolor printing or precise line images.
For obtaining photographic light-sensitive materials undergoing less dimensional change, that is, having excellent dimensional stability, a technique of defining the ratio of the thickness of the hydrophilic colloid layer(s) and the thickness of the support is described in U.S. Pat. No. 3,201,250 and a technique of incorporating a polymer latex in the hydrophilic colloid layer(s) is described in Japanese Patent Publication Nos. 4272/64, 17702/64, 13482/68, and 5331/70 and U.S. Pat. Nos. 2,763,625, 2,772,166, 2,852,386, 2,853,457, 3,397,988, 3,411,911, and 3,411,912. The theoretical basis for the aforesaid techniques is given in J. Q. Umberger, Photographic Science and Engineering, 69-73 (1957).
However, the inclusion of such polymer latexes in hydrophilic colloid layers of photographic materials has a harmful influence on the film strength and abrasion resistance of the hydrophilic layers in processing solutions and the adhesior of these layers to supports in solutions.
A technique of overcoming the aforesaid problems involved with polymer latexes involves using a polymer having an active methylene group reactive with conventional gelatin hardening agents. It is described in U.S. Pat. Nos. 3,459,790, 3,488,708, 3,554,987, 3,700,456, 3,939,130, British Patent No 1,491,701, etc. By the aforesaid techniques, the dimensional stability of photographic materials can be improved to some extent without reducing the film strength and abrasion resistance thereof in processing solutions. However, in multicolor printing or the printing wherein reproduction of precise line images is required, a further improvement of the dimensional stability of photographic light-sensitive materials has been strongly desired.
Also, a technique of improving the dimensional stability of photographic materials by using a support composed of a polyester film, both surfaces of which are coated with polyolefin, is disclosed in Japanese Patent Application (OPI) No. 3627/85 (the term "OPI" as used herein means an "unexamined published application"), but the improvement is insufficient for practical purposes.
Furthermore, methods using hydrazine derivatives for obtaining high contrast photographic characteristics are described in U.S. Pat. Nos. 4,224,401, 4,168,977, 4,166,742, 4,311,781, 4,272,606, 4,211,857, 4,243,739, etc. According to these methods, photographic light-sensitive materials having very high contrast and high sensitivity can be obtained. However, since in these methods the action of increasing contrast by hydrazine derivatives is hindered by using a large amount of polymer latex for improving the dimensional stability of the photographic material, whereby high-contrast photographic characteristics are not obtained, the amount of polymer latex is restricted for obtaining high-contrast characteristics and hence sufficient dimensional stability cannot be obtained.
The aforesaid technique of defining the ratio of the thickness of the hydrophilic colloid layer(s) and the thickness of the support can reduce the degree of stretching or shrinking of unprocessed or processed photographic films by changes in humidity.
However, the dimensional change of photographic films before and after processing steps (development, fix, wash, and drying) which are usually applied to photographic films cannot be prevented. This is because the support for the photographic film stretches by absorbing water in processing but it takes a long period of time to restore the stretched support to its original state even after drying, and the stretch is retained. Accordingly, the dimensions of a photographic film after processing are generally larger than those of the film before processing. This phenomenon is called "the dimensional stability with processing is bad" and is a serious defect, in particular, with photographic light-sensitive materials for printing.
The technique of incorporating a polymer latex in a hydrophilic colloid layer of a photographic light-sensitive material may reduce the stretching or shrinking due to changes in humidity to some extent, but cannot overcome the aforesaid problem since the support of the photographic material is impregnated with processing solution at processing.